On 21/07/2021 11:53, Miroslav Lachman wrote:
On 09/07/2021 13:16, Andriy Gapon wrote:
On 08/07/2021 00:34, Miroslav Lachman wrote:
The question is simple but I cannot find answer - Does FreeBSD support
hot-plug vCPU and hot-add RAM?
Current virtualization platforms support adding CPU cores or additional RAM
without the need to reboot the guest OS. Some of our clients need to add
additional vCPUs or RAM so often that hot-plug and hot-add will be really
useful. If this is not supported on FreeBSD for now, is there any Work In
Progress? Or is there a plan to support it?
I think that those features are not supported and I haven't heard of any WIP.
Thank you for your reply. I know nothing about system internals. Is it too much
work to implement it or just nobody from developers need it thus nobody write
the code? Virtualization is more and more popular these days so I think it will
be useful for many users.
In my opinion, both would be big changes.
At the moment we do not have any support for offlining / onlining CPUs and that
would involve a lot of careful changes like safely updating CPU sets, various
CPU masks, etc.
Ditto for the memory. Updating page arrays, free memory accounting structures,
possibly some memory maps, etc.
Definitely not a weekend project.
--
Andriy Gapon
